1. Field of the Invention
The present invention relates to a micromechanical system and a method for manufacturing a micromechanical system.
2. Description of Related Art
Micromechanical systems are used as sensors and actuators in the automotive field and in consumer entertainment electronics and are typically produced by using surface micromechanical methods. Conductive function layers and insulating sacrificial layers, often containing polycrystalline silicon and oxides, are deposited on a substrate wafer. Movable micromechanical elements are fabricated from a function layer and are exposed mechanically by dissolving away the sacrificial layer underneath.
Multichannel sensors, which are suitable for detection of measured variables, for example, accelerations in multiple directions in space, are implemented by single-channel sensors situated side-by-side on a substrate according to the related art. This is described in published German patent document DE 100 64 494 A1, for example. This side-by-side layout requires a great deal of space. Alternatively, it has been proposed that a multichannel sensor having a single seismic mass movable in multiple directions in space be designed. This embodiment has the disadvantage that it results in increased crosstalk between the individual channels.
It has also been proposed that micromechanical sensors be fabricated from substrates having more than one function layer. Published German patent application document DE 10 2007 060 878 A1 describes a single-channel micromechanical sensor element fabricated from a substrate having a conductor path layer and two functional layers. Published German patent application document DE 10 2006 032 195 A1 describes a corresponding manufacturing method.